Lifting weights is obviously great for your strength, but it can also boost your brain power, improve your immune system, and even reverse signs of cellular ageing. Michael enlists Jenny, a self-confessed weight lifting novice, to try strength training at home using milk bottles and a sturdy rucksack. He speaks to Dr. Teresa Liu-Ambrose at University of British Columbia, Canada who has recently found that strength training can lead to better memory. She reveals how activating your muscles can release special chemicals called myokines which astonishingly, can travel around the body and cross your blood-brain-barrier where they can have beneficial effects on your brain.